Hyperon-nucleon interaction and meson exchange

We present first results of our general program which is to construct meson-exchange potentials for hadronic systems involving stange particles, i.e. for KN and AN. We proceed along the same guidelines which have been successfully applied in deriving the (latest version of the) Bonn NN potential, namely to keep the important recoil and nonlocal structure and to use a comprehensive set of diagrams without introducing any fictitious contribution. For KN we show that single vector-meson (..omega..,p) exchange already provides a fair description of the data except for the isospin-1 P/sub 3/2/ wave. This partial wave is remarkably improved by adding a specific higher-order process involving ..delta..K intermediate states. For the ..lambda..N system we demonstrate the inadequacy of a nonrelativistic treatment of the ..lambda..N interaction and point to the strong interplay between K and K*-exchange in the tensor channel, which is even stronger than for ..pi..- and p-exchange in the NN system

Das steuerpolitische Dezemberfieber: Steuergesetzgebung in Deutschland von 1951 bis 2004

Public complaints about the growth, complexity and volatility of tax legislation abound. Against this background, the present article gives an account of the quantitative development of tax legislation in post-war Germany. We find that the legislative output did not increase over the decades. In general, the output is higher during the 12 months before a federal election than during the first 12 months after. Furthermore, the legislative output is not affected by a split majority in the upper and lower houses. Finally, we find that an increasing fraction of this legislation is passed in December. This growing "December fever" reduces the available time to adapt for taxpayers, tax-lawyers, and tax authorities and is a plausible explanation of the growing discontent with tax policy. Copyright 2007 die Autoren Journal compilation 2007, Verein für Socialpolitik und Blackwell Publishing Ltd.